Which characteristics of a graph tell you that it represents a proportional relationship?

Consider 6x2 + 6x + 1. which term immediately tells you that this expression is not a perfect square trinomial? justify your answer

Christina can paint 420 square feet in 105 minutes. which unit rate describes the scenario?

Acar started driving from city a to city b, distance between which is 620 miles, at a rate of 60 mph. two hours later a truck left city b and started moving towards city a at a rate of 40 mph. how many hours after the truck's departure will the two meet?